A conventional stereoscopic image display apparatus for displaying a stereoscopic image on a display screen is shown in FIG. 7, uses a pair of image signals generated by two video cameras 42 and 43 located at a predetermined distance from an object 41 at with predetermined separation therebetween. The pair of image signals is then displayed on a single display screen 46 by two display devices 44 and 45, respectively, overlapping each other.
However, such conventional stereoscopic image display apparatuses have drawbacks in that they require two separate projections in order that two images, i.e., the left and right images, may be overlappingly displayed on a single display screen. The stereoscopic image display apparatus is thus bulky and complicated.
It is desired to provide a stereo projection optical system which can overcome the above-described deficiencies.